Outside pipe cutter



7 D. H. REED OUTSIDE PIPE-CUTTER April 1, 1947.

Filed Aug. 24, 1.945 2 Shets-Sheet 1 DEMPSON I-LPEED.

INVENTOR. (ya/IR *7E4' d? A's-re NEY April '1, 194?. D. H. REED OUTSIDE PIPE-CUTTER 2 Sheets-Sher. 2

Filed Aug. 24, 1945 R m m MW b R i m N m cm A O S wq m D V.

Patented Apr. 1, 1947 UNITED STATES PATENT" OFFICE.

OUTSIDE PIPE CUTTER Dempson I I.'Reed,,Houston, Tex. 1

Application August .24, 194'5,'Serial No. 612,340

11 Claims. 1

The. invention relates to an outside pipe-cutter .of'the compensating typeso as to provide a graduated frictionaldrive to accomplish the cuttin action.

The present pipe cutter is in .the nature of an improvement over that shown in my prior patent, 2,213,049 issued August 27, 1940.

In the operation of an outside pipe-cutting .tool in a well bore .for the purposenoi severing pipe great difficulty is encountered due to various conditions such as the particular position or inclination of the pipe, the hardness of .the material of the pipe, and the fact that thetool must operate in a medium of drilling fluid or abrasive slush. An outside pipe-cutter in amajority of instances is usedin cutting off sections -.of drill pipe which is usually made of high carbon steel having a relative .thick wall so that it isdifiicult to out and thetool must be operated in the annularspaoe around the outside of the pipebeing cut and within the confines of the diameter of the well boreorcasing therein.

With the foregoing conditions in mind, it is obvious that an adjustment of the cutters for one set of i circumstances may notcause the cutter .to operate as effectively under other conditions .and that a setting of the cutters before the tool is, lowered into the wellbore may difier asebeing an improper setting when the conditions .down in the well are encountered. It is thereforedesirable to provide atool wherein the power tend- .ing'tojadvance the cutters may be adjusted or varied, depending upon the conditions'encountered because a driving force whichwould advance the cutters at one location or againstone portion of the pipe. might be entirely inadequate when used in making another ut.

It is therefore meet the objects of the invention to provide an outside pipecutting tool wherein the frictional driving force tending to .advance the cutters to perform 'thecuttingac- .tionrmay beadjusted;byimanipulationof the tool while it is in positioninthe well bore.

Another. object :of :the :inventionris to provide an .outside pipe-cuttinggtool wherein the driving mechanism foriadvancing the. cutters may be adjusted for increasing the driving .forcezby. manipulationof the tool in :the well here either before or during the cutting :action.

.Another object of .the invention istoproyide v.adriving mechanism .ior advancing the cutters in :.an outsiden De-cutting tool which can be ad- ,justed by backing up the tool.

still another object of .the invention. isv to provide a compensating driving mechanism for outoutside pipe cuttin .tool 5Lis thus 2 side pipe-cutters wherein the friction driving rings are so constructed as to be unaiiected by the flow of flushing fluid.

Still another object of the invention is to provide an anchor device for outside pipe-cutting tools which may be operated to move into pipe engaging position by the application of hydraulic pressure.

Another object of the invention is to provide a control ,,mechanism for advancing the outside pipe-cutters against the pipe said mechanism including a sprin loaded compensating friction drive.

Other and further objects of the invention will be readily apparent when the following description is considered in connection withthe accompanying drawings, wherein:

Fig. 1 shows the outside pipe-cutting tool in vertical elevation with :one quarter cut away to illustrate an internal arrangement of the parts.

.Fig. 2 is'an .enlargedsectional view ofthe pipe- .cutter. anchorin mechanism.

Fig. 3 is a transverse-section through the tool illustrating the 'spllned arrangement ofthe parts to effect rotation of onepart with respect'to the other.

.Fig. 4 is a vertical sectional view illustrating the spring loaded compensating adjustment for the driving mechanism.

.orrother this pipe 2 has become .lodgedor stuck .in the well .boreand cannot beremoved. The sing lowered over the pipe 2 witha viewofsevering the upper section .6 of the pipe from the lower portion '1 which is lodged in the hole.

This; pipe cutting tool .5 is arrangedtobelowcred into the well bore andimanipulated by an operatingpipefi which. is threaded at 9 into the body or housing o-fwthe-tool It. This housing is arrangedto .contain'the various mechanisms of .the cutting ,tool and .at the upper end .thereare arranged a plurality of dogs or pipe "engaging members II which are mounted on a bushing l2 so as to seat on the shoulder |3 thereof. These dogs are normally pressed inwardly by a leaf spring l4 and have a tooth inclined edge l5 thereon to engage against the shoulder l6 of the coupling or tool joint 3.

The springs |4 normally urge these dogs or engaging members inwardly toward the pipe but they are enabled to move backwardly so as to snap by the collars 3 which are passed on the way down.

Fig. 1 shows this anchor mechanism as having been locked or latched in pipe engaging position by moving the flange 20 of the sleeve 2| in behind the up-per end of the dogs. This is accomplished by the application of hydraulic pressure to the upper surface 22 of the sleeve 2!. This sleeve is normally urged upwardly by the coiled spring 23 seated on the shelf 24 carried by the cylinder 25. Th s cylinder is in turn retained in position by the set screws 25 on the bushing 21 as best seen in the left hand side of Fig. 2. Normally th flange 20 will be spaced above the upper end of the dogs due to the force of the coil spring 23 so that the dogs can slip past the cduplings 3. When it is desired to set the tool a pump pressure through the operating pipe 8 will be increased so that the resistance to flow downwardly through the tool will be applied to the surface 22 on the upper end of the sleeve 2|. In this mannertheflange 2|] will move in behind the dogs to accomplish the locking thereof so that a subsequent upward pull on the tool to effect the cutting action will not dislodge the tool because the anchor mechanism will be securely locked.

This anchor mechanism, including the bushing I2, is supported on the anti-friction bearings 28 supported upon a rib 23 of the housing l0.

Threaded to the bushing l2 at 35 is the driving skirt projecting below the rib-23. This driving skirt has an off-set 32 thereon which is arranged to have th set of friction rings 33 raised upwardly against its lower surface. These friction rings may be provided in any desired number and are offset in size and provided with transverse grooves or slots 36 as best seen in Fig. 4. These slots and offset sizes permit the flow of fluid past the rings in actual use so that there will be no building up of hydraulic pressure on the rings, which might interfere with the frictional resistance or drive as will be later explained. These rings are supported upon the shoulder 34 of the driving collar 35. This driving collar is movably arranged within the housing i0 and is threaded at 31 to a compensating ring 38 which rides on the surface 39 of the nipple 4|) which is threaded at 4| to the housing Hi. The nipple 43 has a plurality of upstanding pins 4| thereon best seen in Fig. 6 which are arranged to b received in the notch 42 of the pawl 43 which is hinged at 43' on the compensating ring 38.

In this manner when the housing I3 is rotated by the operating pipe 8, the pins or studs 4| will move in an accurate path beneath the pawls 43 while the compensating ring 38 is rotated with the housing at a slower rate, dependent upon .the friction between the fritcion rings 33. The driving collar 35 due to the threads 31 will have a tendency to rotate with the compensating ring and in this manner the shoulder 34 will tend to carry the friction rings 33 around with it.

7 In order to vary the friction driving force imparted to the driving collar 35 by the friction rings 33, the compensating rings 38 has an antifriction bearing 43 thereon which supports a plurality of coil springs 44. These coil springs urge the ring 45 upwardly toward the shoulder 34. This ring 45 carries a plurality of studs 45 projecting through the openings 41 in the shoulder 34 bearing against the lower surface 43 of th lowermost one of the friction rings 33. In this manner there will be a spring loaded compressive force applied to the friction rings tending to compress them together and increase the frictional resistance to sliding. It seems obvious that by varying the vertical position of compensating ring 38 by relative turning between such ring and the. pins 4| that the ring will be raised du to the threads 31, Any upward movement therefore will increase the compression on the springs 54 and consequently increase the frictional driving effect on the shoulder 34 and the driving skirt 35.

Fig. 3 shows every other one of the rings 33 as being provided with notches on the outer periphery to engage corresponding splines in the driving collar 35 while the alternate rings will be splined on the inside of the periphery to engage the driving skirt 3|. In this manner half of the rings will be held stationary with the driving skirt and half of them will be compelled to move with the driving collar. p

The driving collar 35 is splined into the driven member 50 which is threaded with a coarse thread 5| into the nipple 4D. This member 53 is thus arranged for relative vertical movement due to these threads 5| but is compelled torotate with the driving collar 35. If this assembly rotates as a unit, then the driven member 50 will not negotiate any vertical movement. 7

This driven member 50 has circumferentially spaced thereon the cross pins 52 upon which'are mounted the links 53 for pivoting movement. These links are in turn pivoted at 54 with the cutters 55 which are carried in the cutter arm 56 pivoted at 5! in the housing H] of the tool.

If the driven member 55 moves downwardly due to the relative turning between such -r nember and the nipple 40, then a block portion 55 thereon is arranged to slide on the surface Bil on the cutter arm 55 so as to cause relative sliding movement from the position of Fig. 1 to the position of Fig. '1 when the cutter is fully advanced. The pin 54 has a flattened side or area 52 thereon as seen in Figs. 1 and '7 which serves to lock thev cutter 55 against any tilting movementwhere it bears against the surface of the block 59.

The links 53 prevent the cutters from advanc-' ing more than the predetermined amount at which the driven member moves downwardly so as to prevent gouging of the pipe. H

It seems obvious that with the foregoing construction, ready adjustment of the frictional driving action can be had because when the out is started, and if the operator finds that'the-resistance to cutting is such that the cutters'do'not advance, it is only necessary'for him to stop the clockwise rotation of the tool and back it up a desired amount so as to cause the pawls '43 to click over the pins or studs 4|;

tional driving force can thus be adjusted to apply the desired force tending to advance the cutters to negotiate the cut iii in the pipe 2.

Broadly the invention contemplates a compensating outside pipe-cutting tool where the frictional driving force tending to advance the cutters can be adjusted while the tool is in the well bore, depending upon the resistance encountered.

What is claimed is:

1. An outside pipe-cutting tool including a housing, means to anchor said housing against upward movement on the pipe being out including means to contact the pipe, and means movable by the flow of liquid pressure in the tool to move said anchor means into firm biting engagement with the pipe.

2. An outside pipe-cutting tool including a housing, means to anchor said housing against upward movement on the pipe being cut including means to contact the pipe, lock means movable by the flow of liquid pressure in the tool to move said anchor means into engagement with the pipe, and spring means to release said look upon reduction in the flow of liquid.

3. An outside pipe-cutting tool including a housing, means to anchor the tool against upward movement on the pipe, pipe cutting members in the housing, a friction driving means operable against said anchor means to advance said outter to cut the pipe, including a plurality of friction rings.

4. An outside pipe-cutting tool including a housing, means to anchor the tool against upward movement on the pipe, pipe cutting members in the housing, a friction driving means operable against said anchor means to advance said cutter to cut the pipe, including a series of friction rings, and an additional means to adjust the frictional pressure of said rings to vary the driving force advancing said cutter.

5. An outside pipe-cutting tool including a housing, means to anchor. the tool against upward movement on the pipe, pipe cutting members in the housing, a friction driving means operable against said anchor means to advance said cutter to cut the pipe, including a series of friction rings, and an additional means to adjust the frictional pressure of said rings to vary the driving force advancing said cutter by backing up the tool relative to said anchor means while such means is engaged.

6. An outside pipe-cutting tool including a housing, an anchor to engage the pipe being cut so as to position the tool, cutters in the housing, and a friction drive to advance said'cutters including means to adjust such drive while the tool is in cutting position in the well.

7. An outside pipe-cutting tool cutter driving construction including an anchor to engage the pipe, cutters to cut the pipe, and a friction drive between said anchor and cutters including a plurality of friction rings, a drive sleeve to be moved longitudinally by said rings to cause ad vance of the cutters, and means to adjust the frictional pressure on said rings.

8. An outside pipe-cutting tool cutter driving construction including an anchor to engage the pipe, cutters to cut the pipe, and a friction drive between said anchor and cutters including a plurality of friction rings, a drive sleeve to be moved longitudinally by said rings to cause advance of the cutters, and means: to adjust the frictional pressure on said rings, including a spring.

9. An outside pipe-cutting tool cutter driving construction including an anchor to engage the pipe, cutters to cut the pipe, and a friction drive between said anchor and cutters including a plurality of friction rings, a drive sleeve to be moved longitudinally by said rings to cause advance of the cutters, and means to adjust the frictional pressure on said rings, including a spring and means to adjust the pressure of said spring against the rings.

10. An outside pipe-cutting tool cutter driving construction including an anchor to engage the pipe, cutter to cut the pipe, and a friction drive between said anchor and cutters including a plurality of friction rings, a drive sleeve to be moved longitudinally by said rings to cause advance of the cutters. and means to adjust the frictional pressure on said rings, including a spring and means to adjust the pressure of said sprin against the rings while the tool is in use in a well.

11. An outside pipe-cutting tool cutter driving construction including an anchor to engage the pipe, cutters to cut the pipe, and a friction drive between said anchor and cutters including a plurality of friction rings, a drive sleeve to be moved longitudinally by said rings to cause advance of the cutters, and means to adjust the frictional pressure on said rings, said rings having recesses therein to allow the flow of fluid between and around the rings so that such fluid will not affect the frictional pressure on the rings.

DEMPSON H. REED.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Nu ber Name Date 2,213,049 Reed Aug. 2'7, 1940 2,325,104 Brown July 2'7, 1943 

